series, the cone is more or less obtuse ; but in general it is expanded,
more or less trilobate, or dentated along the margin of the crown.
In the Polychrus, the anterior score of teeth are simple, slightly-
recurved and obtuse; the remainder are straight, compressed and
tricuspid. The pterygoid teeth forma single row on each bone, and
are short and conical.
In the Urostrophus Vautieri (d . and b .) the upper jaw has forty-
six, or forty-eight teeth ; the lower jaw forty or forty-two teeth : the
anterior ten or twelve, are conical with obtuse apices in both jaws; the
rest are tricuspid. The pterygoid teeth are six or eight in number
in each bone, and present the form of moderately wide cones.
The Anolians have the same anterior conical, and posterior compressed
tricuspid teeth as in the previous genera; but the latter are
relatively fewer in many of the species : in Anolis loysiana, for example,
out of fifty-four teeth in the upper jaw only the eight or nine
posterior ones are distinctly compressed and tricuspid : and this form
is restricted to the hinder six or seven of the forty premandibular
teeth. In the Anolis chloro-cyaneus fourteen of the sixty maxillary and
twenty of the fifty-six premandibular teeth are tricuspid | these are as
usual at the posterior part of the series.
In the Anolis Carolinensis four or five of the posterior tricuspid
teeth are sensibly larger than the rest. In the Anolis alligator
(Lacerta Umaculata, Shaw), there are three or four short hut strong
teeth on each pterygoid hone. The Anolis chamceleonoides resembles
the chameleons not only in external appearance, but in its dentition,
in so far as that none of the teeth present the tricuspid form : the
thirteen anterior ones are pointed, the others simply obtuse : there are
sixty two upper and fifty lower teeth in this species.
The genus Chamceleopsis (Corythophanes, Boie) has the posterior
teeth tricuspid as in the ordinary Anolises.
The dentition of the Basilisks differs little from that of the Anolis ;
the posterior teeth are rather trilobate than tricuspid: the anterior ones
are small, circular, pointed and slightly curved | there are generally
from five or six conical teeth on each pterygoid bone, but in the
Mitred Basilisk there are twelve teeth in each of these rows.
In the Aploponoti, the pterygoid teeth are arranged in two series on
each side.
The Amblyrhynchus, a genus which is somewhat remarkable for
the marine habits of at least one of the species, (.Amblyrhynchus ater)
whose diet is sea-weed, (1) has the tricuspid structure well developed
in the posterior teeth, and these teeth are somewhat thicker than in
the preceding Iguanians.
The typical genus of the present family of Saurians is characterized
by the crenate or dentated margin of the crown of the maxillary
and premandibular teeth, a few of the anterior small ones excepted ;
the pterygoid teeth are arranged in two or three irregular rows, resembling
somewhat the ‘ dents en cardes’ of fishes.
In the full-grown Iguana tuberculata there are from forty-seven to
forty-nine teeth in both upper and lower jaws : the number is less in
young subjects. The double row of pterygoid teeth are in close order
on each side.
In the horned Iguana {Metopoceros cornutus, d . & b ., PI. 70
figs. 6 and 7) there are about fifty-six teeth in both the upper and
lower jaw, of which the four first are conical and slightly recurved ;
the twelve succeeding teeth are somewhat larger in size, with more
compressed and expanded crowns ; the rest are triangular, compressed,
with dentated margins. The inner surface of the crown of the tooth
is simply convex and smooth, the outer surface traversed by a median
longitudinal broad obtuse ridge.
There is a single row of small teeth implanted in each pterygoid
bone (PI. 68, fig. 2 , d). No Iguanian lizard has teeth on the palatine
bones. (2)
The teeth of the Cycluri differ from those of the Iguanas in being
trilobate or bilobate and not crenate at the margin : the pterygoid
teeth are in a single row.
In the Iguana cyclura of Cuvier there are thirty-six teeth in the
(1) This species, and probably all the known AmUyrhynchi or blunt-nosed Iguanæ, inhabit
the islands of the Gallopagos group ; their habits have been well elucidated by Mr. Darwin,
(Voyage of the Beagle, vol. lii. p. 466) : in specimens which he dissected he found the stomach
loaded with minced sea-weed.
(2) For the purposes of zoology the expression ‘ palatine teeth’ serves in general sufficiently
to denote their existence, whether they be vomerine as in the Batrachia or pterygoid as in the
Saurians; it is in this sense doubtless that the learned authors of the Erpétologie Générale
describe the teeth of the Iguana and other Lacertians as being situated onthe « os palatines.’
R 2